Monsanto's website states, "There is no need for, or value in testing the safety of GM foods in humans." This viewpoint, while good for business, is built on an understanding of genetics circa 1950. It follows what's called the "Central Dogma" (PDF) of genetics, which postulates a one-way chain of command between DNA and the cells DNA governs...

However,

Chinese researchers have found small pieces of ribonucleic acid (RNA) in the blood and organs of humans who eat rice.... provid[ing] the first example of ingested plant microRNA surviving digestion and influencing human cell function.

The name of the report hints at what it is all about:
... evidence of cross-kingdom regulation by microRNA

The "cross-kingdom" meaning "between the plant kingdom and the mammal kingdom", or, in other words, there is now the scientifically proven possibility that the genetic information of genetically modified foods will not be destroyed by the acids in the stomach nor by the digestive process, but will be able to be transferred into the bloodstream, and by this conduit to flow to all parts of the body!
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